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CSS

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HTML 

              
                <div class="card card--min">
  <header class="card__header">
    Min
  </header>
  <div class="card__body">
    <p>Imagine that we want this card to occupy 70% of the width on small screens, but never to be bigger than 700px.
    <p>We can do:</p>
    <pre><code class="lang-css">
  width: 70%;
  max-width: 700px;
    </code></pre>
    <p>
      We can simplify using: <span class="code"></span>
    </p>
    <pre><code class="lang-css">
  min(700px, 70%);
    </code></pre>
    <p><em>You can add as many values as you whan't (if it has sense). Usually all with different units. The order does not matter.</em></p>
  </div>
</div>

<div class="card card--max">
  <header class="card__header">
    Max
  </header>
  <div class="card__body">
    <p>Imagine that we want this card to occupy 200px on small screens, but when we make the screen big enough, it has to occupy the 30% of the screen.</p>
    <p>We can do:</p>
    <pre><code class="lang-css">
  width: 30%;
  mix-width: 200px;
    </code></pre>
    <p>
      We can simplify using:
    </p>
    <pre><code class="lang-css">
  max(200px, 30%);
    </code></pre>
    <p><em>You can add as many values as you whan't (if it has sense). Usually all with different units. The order does not matter.</em></p>
  </div>
</div>

<div class="card card--clamp">
  <header class="card__header">
    Clamp
  </header>
  <div class="card__body">
    <p>Imagin that we want to have an element that occupies the 50% of the width, but never less than 300px nor more than 700px.</p>
    <p>We can do:</p>
    <pre><code class="lang-css">
  min-width: 300px;
  width: 50%;
  max-width: 700px;
    </code></pre>
    <p>
      We can simplify using: <span class="code"></span>
    </p>
    <pre><code class="lang-css">
  clamp(200px, 50%, 700px);
    </code></pre>
    <p><em>It works only with 3 values.</em></p>
  </div>
</div>

<div class="card">
    <header class="card__header">
        Interesting video (by Kevin Powell):
    </header>
  
    <div class="card__body">
      <iframe class="youtube" width="560" height="315" src="https://www.youtube.com/embed/U9VF-4euyRo" frameborder="0" allow="accelerometer; autoplay; encrypted-media; gyroscope; picture-in-picture" allowfullscreen></iframe>
    </div>
</div>

<div class="card card--warning">
  <header class="card__header">
    Warning
  </header>
  <div class="card__body">
    <p>I wouldn't recomend using it yet, it is too soon: <em>e.g.: Firefox ERS does not support min(), max() or clamp()</em>. Nevertheless, I think it is interesting to know how it works.
  </div>
</div>

<!-- I'm using prism for "prettier" code (syntax highlighting). See codepen settings. -->
!

CSS 

              
                .card--min {
  width: min(700px, 70%);
}

.card--max {
  width: max(200px, 30%);
}

.card--clamp {
  width: clamp(300px, 50%, 700px);
}

/* Other stylings */
:root {
  --clr-primary: #ee6352;
  --clr-body: #333;
  --clr-bg: #ddd;
  --clr-bg-warning: #ffe0b1;
  --clr-shadow: #0003;
}
body {
  font-family: basic-sans, sans-serif;
  margin: 0;
  display: flex;
  flex-direction: column;
  align-items: center;
  background: var(--clr-bg);
  color: var(--clr-body);
  
}

.card {
  margin: 3rem 0;
  background: white;
  padding: 2em;
  box-shadow: 0 3px 6px var(--clr-shadow);
  transition: box-shadow 0.1s ease-in-out;
}
.card:hover {
  box-shadow: 0 1px 2px var(--clr-shadow);
}

.card--warning {
  margin: 3rem;
  background: var(--clr-bg-warning);
}
.card__header {
  color: var(--clr-primary);
  font-size: 1.7rem;
  font-weight: 900;
  margin: 0 0 .5em;
  padding: 0;
}
.youtube {
  width: 100%;
}

.hidden {
  display: none;
}
!

JS
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999px

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